The present invention relates to low molecular weight acrylic polymers.
The preparation of low molecular weight acrylic polymers for use in formulating low volatile organic content (VOC) compositions has become increasingly important. It has been found, however, that decreased molecular weight, in and of itself, is not a total solution because film properties such as hardness and durability are generally detrimentally affected as the molecular weight of the polymer decreases. This phenomenon has been explained on the basis of deficient functionality. That is, that low molecular weight polymers with fewer than two functional groups cannot contribute to a crosslinking network and thus tend to give poor film properties.
The art has attempted to address these difficulties in a number of ways, for example, U.S. Pat. No. 4,075,242 which discloses a polymerization process conducted at temperatures in excess of about 150.degree. C. and in the presence of a high boiling solvent as a polymerization medium, the preferred being benzyl alcohol. Often, however, it is desirable to prepare an acrylic based coating composition which has modified properties, but yet, still has a low VOC. There is a need for such a method of preparation and the resultant products.